On 15/12/11 16:38, Keegan Holley wrote:
2011/12/14 oliver rothschild <orothschild@gmail.com>
Thanks to all who responded to my clumsy first question (both on matters of etiquette and technology). The group I work with (we are a small project acting as a last mile provider) was in the midst of deploying this solution when I posed the question. We put the single mode Juniper SFPs (LX) on to a run of approximately 1670 meters.
How did you end up with a MM run this long? SX optics are only rated at 500 meters at best. Even with mode conditioning jumpers more the 1km is a risk. I'm glad it held up during testing though. Just out of curiosity did you purchase dark from a provider? Is it inside of a building?
Um.. check that. https://en.wikipedia.org/wiki/Multi-mode_optical_fiber "Typical transmission speed and distance limits are 100 Mbit/s for distances up to 2 km (100BASE-FX <https://en.wikipedia.org/wiki/100BASE-FX>), 1 Gbit/s to 220--550 m (1000BASE-SX <https://en.wikipedia.org/wiki/1000BASE-SX>), and 10 Gbit/s to 300 m (10GBASE-SR <https://en.wikipedia.org/wiki/10_Gigabit_Ethernet#10GBASE-SR>)." The old OM1 installations I used to work on started out as 10Mbit hubbed ethernet links and on the odd occasion would run out to close to 2km within a campus. They were progressively upgraded with the flow of: 10FX on 3Com Linkbuilder Kit 100FX on 3Com Corebuilder Kit and Allied Telesyn 100FX Media converters 1000SX on a variety of 3Com, Nortel and Cisco kit out to ~220m 1000LX via Mode-Conditioning out to ~900-1000m. The OM1 only got retired when the distance was >900m or there was budget to put new fibre on the run, in which case we ran SMF and rigged LX drivers. Mark.